Dog Age by Breed Calculator
Pick your dog’s breed to convert its age to human years: the breed’s AKC weight range sets the small, medium, large or giant aging chart.
How fast a dog ages depends mostly on its size, and size depends largely on breed. Pick your dog’s breed, or a mixed-breed size, and this calculator takes the breed’s typical adult weight from the AKC, places it in the small, medium, large or giant column of the dog-to-human age chart and converts your dog’s age. If your dog is much bigger or smaller than its breed norm, enter its weight and that is used instead.
How to use this tool
- Choose the breed, or a mixed-breed size if your dog is a mix.
- Enter your dog’s age in years and months.
- Optionally enter your dog’s healthy adult weight to override the breed’s typical weight.
- Read the human-equivalent age and the year-by-year table for that size.
Formula
Size group from adult weight: small ≤ 20 lb, medium > 20 to 50 lb, large > 50 to 100 lb, giant > 100 lb; human age is read from that group’s column of the chart
Breeds whose AKC weight range straddles two groups are placed by the middle of the range, so the Australian Shepherd (40–65 lb) counts as large and the Rottweiler (80–135 lb) as giant. Ages between whole years are interpolated, and the epigenetic estimate, 16 × ln(age) + 31, is shown for comparison.
Example
A 10-year-old Labrador Retriever (typically 55–80 lb, so large) is about 66 in human years. A Chihuahua of the same age is about 56, while a 10-year-old Great Dane is about 79.
Frequently asked questions
Why does a Great Dane age faster than a Chihuahua?
Giant breeds have much shorter average lifespans than toy breeds, so by middle age each calendar year covers more of their life. The chart reflects this by adding about 7 human years per year for giant dogs, against about 4 for small dogs.
My dog is a mix. What should I choose?
Pick the mixed-breed size that matches its adult weight, or enter the weight directly. Weight is what the chart is based on.
My breed is not listed.
Choose a breed of similar adult weight, or just enter your dog’s weight; the result will be the same as for any breed of that size.
How accurate is this?
It is a size-based estimate. Genetics, body condition and health matter as much as breed, so ask your vet how your own dog is ageing.
Sources
This tool gives an estimate for general information only. It is not financial, tax, legal or medical advice — check with a qualified professional before you rely on the result.
Last updated: 2026-10-30